1. Field of the Invention
The present invention relates to an electrically conductive polymer, a semiconductive composition using the electrically conductive polymer and a semiconductive member or electrophotographic equipment, especially to be used for constituting members of electrophotographic equipment such as a charging roll.
2. Description of the Art
Generally, it is possible to make a pi-electron conjugated polymer such as polyaniline into an electrically conductive polymer by doping by means of a dopant. However, solubility of the electrically conductive polymer to solvent is deteriorated due to a dopant.
Thus, when the pi-electron conjugated polymer is made into an out-of-doping state without use of a dopant, the polymer is given solubility and be soluble into a solvent so as to be available for use as a coating. For example, when elaborating polyaniline in an out-of-doping state, the thus obtained polyaniline is soluble into N-methyl-2-pyrrolidone (NMP), very high boiling-point solvent, so as to be used as a coating (see Japanese Unexamined Patent Publication No. 2001-324882).
However, since a doping by means of a halogen gas or the like is indispensable as a post-treatment to impart electrical conductivity to the polymer in the above-mentioned method, uniform control is difficult and process becomes complicated. Alternatively, it is possible to impart solubility to the polymer by introducing long-chain alkyl substituent groups into a monomer main chain such as aniline instead of making into an out-of-doping state. However, the monomer as a row material is expensive to render a restriction for industrial use. As described above, it is a current situation that an electrically conductive polymer available at low-cost and superior both in electrical conductivity and solubility is still not available. Under such circumstances, such an electrically conductive polymer has been strongly demanded.
In view of the foregoing, it is an object of the present invention to provide an electrically conductive polymer available at low-cost and superior both in electrical conductivity and solubility, a semiconductive composition using the electrically conductive polymer and a semiconductive member for electrophotographic equipment.